She joined the "A Little Night Music" cast after a call from Sondheim himself.

In February, the Post reported that Vanessa Redgrave and her daughter, Natasha Richardson — who died tragically after a skiing accident a month later, in March — had expressed interest in the revival's roles after performing them at a benefit concert for the Roundabout Theatre Company in January.

The role of Desiree doesn't include much singing, but Catherine will have the chance to perform one of Sondheim's most famous songs, "Send In the Clowns."

While she may be heading for the stage, the star's still making moves in Hollywood. Up next, Catherine stars in romantic comedy "The Rebound" alongside "The Hangover" star Justin Bartha. The film is due later this year.